Abstract
This study compared male amateur basketball players with asymptomatic patellar tendon tendinopathy (ASYM) to healthy controls (CON) during simulated games to explore the differences in patellar tendon force (PTF) and related metrics. Data on kinematics, kinetics, and electromyography were collected from 24 participants, comprising 12 in the ASYM group and 12 in the CON group, performing a stop-jump task in four stages (1(st), 2(nd), 3(rd), 4(th)). A musculoskeletal model was used to calculate PTF, and Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA) identified significant variables. In the first three stages, the ASYM group showed significantly greater PTF and the ankle discrete relative phase (ADRP) than the CON group, with differences of 0.98, 0.79, 0.81kg•BW(-1) (p < 0.001) and 7.34°, 11.24°, and 2.49° (p < 0.05), respectively. In the last three stages, the ASYM group had a higher knee co-activation index (KCAI) than the CON group, with differences of 0.33, 0.28, and 0.25 (p < 0.05). Correlations between PTF and the ADRP and between PTF and the KCAI were the highest, at 0.58 and 0.61, respectively. The OPLS-DA model effectively distinguished between the groups, suggesting potential applications in tendon health monitoring. The findings suggest that elevated PTF may be linked to tendinopathy in male amateur basketball players, highlighting the importance of comprehensive strategies, such as improving ankle symmetry and optimizing muscle coordination to mitigate tendon load and injury risk.